 <ul class="nav nav-tabs" style="margin-left: -1px;">
    <li>
      <a href="{:U('student')}" class="nav_student" >班级学生管理</a>
    </li>
    <li>
      <a href="{:U('student0')}" class="nav_student0">未注册学生</a>
    </li>
    <li>
      <a href="{:U('member')}" class="nav_member">学生位置</a>
    </li>
    <li>
      <a href="{:U('Score/score')}" class="nav_score">学生积分</a>
    </li>
    <li>
      <a href="{:U('initpassword')}" class="nav_initpassword">重置密码</a>
    </li>
  </ul>
 <script>
    $(function () {
        $('.nav_' + "{$now_tab}").parent().addClass('active');
    });
</script>